Yet, as has become clear over the past few years, International Ozone Day is about more than just successful ozone layer protection. Given that many substances that deplete the ozone layer also have global warming potential (GWP), the transition to the use of substances with lower or no GWP has contributed important climate co-benefits over the years. As a result, the Protocol’s agenda has increasingly focused on cross-cutting themes linked with climate mitigation and energy efficiency. From both ozone and climate perspectives, the Protocol is widely recognized as a success.

The World Bank–China Montreal Protocol partnership is a testament to this success. Over the past two decades, it has phased-out more than 219,000 tons of ozone depleting substances from sectors as varied as refrigeration, air-conditioning, foam manufacturing, aerosol production, and fire extinguishing. Since these substances have GWP, the phase-out also avoided the equivalent of 885 million tons of carbon dioxide (CO2) or having the effect of taking 184 million cars off the roads.